8 Replies

I choose Microwave because it can boil the milk in seconds and I read in a post that microwave can heat uniformly without disturbing the milk proteins. So I thought why not build a boiler with microwave and monitor the milk health using pH sensor.

I think the complication is that your sensor wires (i.e. pH and temperature) are stuck into the middle of a microwave field. The sensor wires, and the electronics these wires are connected to, are going to tend to get cooked, along with the milk.

So, if you really want to cook with microwaves, you will have to put some serious thought into methods for to keep your sensors, and connected electronics, protected from microwaves.

Yeah. That might work. It might require some kind of tube-through-a-shield kind of bulkhead fitting. Or maybe just an ordinary bulkhead fitting, that looks like a short length of metal tube, solidly, electrically, connected to the metal oven wall it punches through.

Actually I think there is some mojo like this on the wires that carry the filament current into the body of the oven's magnetron tube. Those wires are insulated from the rest of the metal body of the tube. Essentially the filament is cathode. The metal body is anode.

I should probably draw some pictures of this, but I might not bother.

What I mean by tube through-through-a-shield, is I am imagining some sort of mesh, with small holes, kind of about the same spacing as the mesh used for the see-through area in the oven's door. This mesh is in the middle of the fitting, and the milk has to flow through it.

But the mesh might not be needed, if a short length of metal tubing can act like a waveguide,

https://en.wikipedia.org/wiki/Waveguide_(electroma...

with a lowest allowable frequency (c/(2*d) where d is inner diameter of the tube) that is much higher than that of the actual microwaves bouncing around in the oven.

Although, I don't know how long that short length of waveguide has to be.

It might be that the reason the holes in the see-through mesh, in the oven door, are so tiny is because they have no depth. Those holes are not lengths of waveguide, because they have no length. If that kind of hand-waving argument makes any sense.

Steam heating of food (Milk) is the most efficient heat transfer... Used by major casinos all over the world and coffee milk frothing machines also all over the world..

Microwaves cause molecular friction between the water atoms that are a major constituent of milk and may damage individual milk molecules that are so carefully manufactured in a multi stomached bovine... So I would expect a full bio chemistry PHD detective would need to assist you in evaluating how dangerous you would make your friendly nourishing white liquid with energetic radio waves....